Stock-based compensation (Tables)

3 Months Ended

Mar. 31, 2022

Share-based Payment Arrangement [Abstract]

Schedule of significant assumptions used in determining fair value of options granted

The following table shows the significant assumptions used in determining the fair value of options granted in the three months ended March 31, 2021 and March 31, 2022. The Company granted options covering 771,196 common shares in the three months ended March 31, 2021.

	Three months ended March 31, 2021				Three months ended March 31, 2022
Dividend yield	0.97	%	—	1.08%	0.96	%
Expected life (in months)	84				84
Risk-free rate of interest	1.21	%	—	1.37%	1.71	%
Volatility	26.05	%	—	26.07%	26.29	%

Schedule of stock option activity

A summary of stock option activity during the three months ended March 31, 2022 is set out below:

	Three Months Ended March 31, 2022
	Shares  arising out of options	Weighted  average exercise price	Weighted average remaining contractual life (years)	Aggregate intrinsic value
Outstanding as of January 1, 2022	8,008,296	31.30	6.1	—
Granted	475,695	52.12	—	—
Forfeited	—	—	—	—
Expired	—	—	—	—
Exercised	—	—	—	—
Outstanding as of March 31, 2022	8,483,991	32.47	6.0	101,337
Vested as of March 31, 2022 and expected to vest thereafter (Note a)	7,835,943	31.57	6.0	99,487
Vested and exercisable as of March 31, 2022	3,876,735	24.79	3.8	72,557
Weighted average grant date fair value of grants during the period	14.19

(a)Options expected to vest reflect an estimated forfeiture rate.

Schedule of restricted share units activity

A summary of RSU activity during the three months ended March 31, 2022 is set out below:

	Three Months Ended March 31, 2022
	Number of Restricted Share Units	Weighted Average Grant Date Fair Value
Outstanding as of January 1, 2022	759,507	42.29
Granted	125,786	47.70
Vested	—	—
Forfeited	(2,601)	41.95
Outstanding as of March 31, 2022	882,692	43.06
Expected to vest (Note a)	761,720

(a)The number of RSUs expected to vest reflects the application of an estimated forfeiture rate.

Schedule of performance units activity

A summary of PU activity during the three months ended March 31, 2022 is set out below:

	Three months ended March 31, 2022
	Number of Performance Units	Weighted Average Grant Date Fair Value	Maximum Shares Eligible to Receive
Outstanding as of January 1, 2022	4,583,155	39.40	4,583,155
Granted	1,544,311	44.51	3,088,622
Vested (Note a)	(2,026,900)	34.66	(2,026,900)
Forfeited	(33,962)	43.68	(33,962)
Adjustment upon final determination of level of performance goal achievement (Note b)	28,325	44.01	28,325
Outstanding as of March 31, 2022	4,094,929	43.67	5,639,240
Expected to vest (Note c)	3,013,544

(a)2,026,900 PUs that vested during the period were net settled upon vesting by issuing 1,224,003 shares (net of minimum statutory tax withholding).

(b)Represents an adjustment made in March 2022 to the number of shares subject to the PUs granted in 2021 upon certification of the level of achievement of the performance targets underlying such awards.

(c)The number of PUs expected to vest reflects the application of an estimated forfeiture rate.